Little is known about Yuya Hiruma. He seems to have a bad relationship with his son is as seen by Youichi's constant evading of him. In one instance Youichi even threw away his cell phone after receiving a call from his father. Also Mamori once witnessed Youichi's bag full of cell phones suggesting that he goes through extensive measures to stay out of contact with Yuya.
It is revealed in the manga that Yuya was a chess/shogi champion, which might explain Youichi's keen insight. He played an aggressive style of chess, which he soon gave up after too many loses moving to a safer defensive style. In the end Yuya was unable to make a sufficient amount of wins and was forced to retire. It seems that his son resents Yuya for obediently accepting failure, which gave him an obsession for winning and an undying will to maintain his own aggressive style.
Yuya is surprised by Youichi's huge amount of faith in his teammates saying that, like him, he used to only believe in numbers and facts. Yuya is happy for his son's development and seems to want a more active role as a father by trying to support Hiruma in his love of football.